Method of producing decorative masonry blocks



s. PA'ruRzo 3,155,529

METHOD oF PEoDUcING DECORATIVE MAsoNEY BLocxs Nov. 3, 1964 Filed Feb. s.1960 ATTORNEY United States Patent O 3,155,529 METHD 0F EPRDUCINGDEQRATWE MASNRY BLOCKS Salvatore Paturzo, Towson, Md., assigner to V.Patin-zo Bro. d; Sons, Inc., Baltimore, Md., a corporation of MarylandFiled Feb. 8, 1960, Ser. No. '7,345 7 Claims. (Ci. 11T-S) This inventionrelates to a method of and apparatus for mass-producing decorativemasonry blocks, and to the product thereof, and has for its principalobject the provision of an improved procedure whereby moldedcementitious building blocirs of various shapes and/or sizes, eachhaving one or more decorative and utilitarian faces, may be rapidlyproduced by an uninterrupted series of operations involving asubstantial minimum of manual labor, with consequent material savings incosts.

The blocks manufactured in accordance with the present method may takevarious forms, in one of which they resemble in shape and dimensions thewell known hollow cinder blocks now in wide use in buildingconstruction; however, the aggregates incorporated into the cement orother binding component preferably are of such character as to impart tothe finished blocks a more pleasing, stone-like appearance than isattainable 'oy the use of cinders. @ne or more faces of each block areso processed as to enhance the appearance of the component materialsvisible at such face and at the same time render said face quite smoothand substantially moisture-proof. As a result, not only may the blocksbe employed in lieu of ordinary glazed ceramic tiles in the erection ofdecorative and moisture-proof interior walls, partitions and the like,but if desired they also may be utilized in the construction of exteriorwalls which are subject to exposure to the weather or other normallydeleterious effects, without substantial risk of deterioration resultingfrom suc'n exposure.

In another form the blocks may be provided with transverse openings ofvarious configurations whereby to produce lattice-like and otherornamental open-work effects upon erection.

When set, aggregate-containing cementitious bioclrs produced byconventional block-molding apparatus present exterior surfaces which arerather rough and marked by numerous pores, pits and crevices of Varyingshapes and ranging from approximately pin-hole size up to perhaps aninch in length, which are the result of failure of the cementitiousbinding constituent of the mixture to completely fill the voids betweenat least some of the pieces of aggregate, However, all surfaces of theaggregate pieces are covered with at least a thin coating of saidbinding constituent, with the result that the block faces show virtuallyno color differentation between the aggregate and binder components,regardless of what the true colors of the aggregates may be.

Since the decorative purposes a color contrast usually is desirable, inorder to provide it the present invention contemplates that those facesof he blocks which are to be exposed to View in an erected wall orpartition are initially dressed, as by subiecting them to an abrading orequivalent action which removes the surface material to a depth of say1/16 to Vs of an inch. This not only exposes the true colors of thepieces of aggregate which had been hidden by the binder coating, andtheir contrast to the color of the binder present in the intersticesbetween the aggregate pieces, but also substantially reduces the numberand/ or size of the above mentioned pits and crevices originallypresentin these block faces, thereby rendering such faces more smoothand even. Such openings and depressions as remain in the faces may beeliminated by the treatment thereof with a filling compound, applied in3,l55,529 Fatenteel Nov. 3, 'i964 lCe such manner as not to destroy thecolor ditferentations obtained by 'the initial dressing operation,following which a thin coating or film of a transparent glaze materialis applied to the surface, which moisture-proofs it while preserving andenhancing said color contrast. If desired, the block faces may be tintedor colored prior to the application Of said glaze coating, or thecoloring may be incorporated into the glaze itself-so long as it doesnot destroy the transparency thereof.

In the accompanying drawing forming a part of this speciiication:

FiGURES l and 1A together constitute anelevational view diagrammaticallyillustrating a typical installation for carrying out the present method;

FIG. 2 is a perspective view of one form of block produced thereby; and

FIG. 3 is a perspective view of a form of block suitable for use in theconstruction of open-work walls or partitions.

Referring t0 the said drawing in detail, the method of producingdecorative building bl cks in accordance with this invention is asfollows:

The blocks are initially prepared in a conventional manner, as bymolding a plastic cementitious, aggregatecontaining mixture to thedesired form and size in any appropriate known type of block-moldingapparatus. The said mixture may comprise, for example, a Portlandcement-and-water binder constituent, and one or more discrete aggregatessuch as dolomite limestone screenings, granulated slag, marble and/ orother natural stone chips, etc. Upon removal from the molding machinethe blocks are either kiln or air cured for a time suliicient for themto attain the desired strength, subsequent to which they are subjectedto the following processing constituting the invention.

The cured blocks itl are placed seriaily upon a continuously movingconveyor means lill adjacent the head end thereof, and areuninterruptedly transported thereby past successive stations at each ofwhich certain operations are performed on each block, for the most partautomatically, that result in a completely finished decorative masonryblock such as above described by the time they are discharged from theother end of said conveyor. As diagrammatically illustrated in FIG. l,the iirst of these stations A is a dressing station at which a thinlayer of one face of the block is removed, as by abrasion, so as topresent a relatively smooth surface. The dressing station may comprise arotating carborundum or other abrasive wheel l2 which is water-cooledduring the Vgrinding operation. During the grinding, portions of theaggregates at the block face being operated upon are ground oif wherebythe natural colorings of such aggregates are exhibited, and as abovermentioned this operation also materially reduces the number and size ofthe pits and other cavities appearing in the block face.

From the dressing station the block is carried to a station B at whichaplastic or semi-fluid filling material 13 is applied to the blockface,-Whereby to eliminate substantially all remaining openings and/orcavities. rThe said filling material may comprise a mixture of cementasbestos and water, .which is spread over said block face and thoroughlyworked into the pores and cavities thereof, as by means of spongyorother suitable elements 14 pressurally engaged with the face of theblockas it passes beneath them, whereby to produce a surface substantiallydevoid of openings and depressions.

The block is next moved to a station C whereat any excess of thepore-filling compound is removed. This may be conveniently accomplishedby a flushing liquid dripped or flowed gently upon the block face, as bya pipe or nozzle l, following which the block is passed beneath asqueegee id at a station D, which removes any free liquid and insuresthat the colorings of the ground faces of the aggregates are notobscured by any of the filling material. The squeegee also exertssomething of a smoothing or troweling action upon the filling materialretained in the depressions in the block face so that when the blockleaves this station its dressed face is quite smooth.

Up to this point the block has been maintained at substantially normalroom temperature but upon leaving the squeegee l it is passed through aheating zone at a station E, wherein it is subjected to a temperaturesuiiicient to remove any remaining moisture quite rapidly. This may beattained by passing the block beneath a battery of open-flame gasburners 17, thereby elevating its temperature and producing a flashevaporation of any moisture remaining on or in the block and/or thepitfilling material. As a result the block leaves the station Evirtually completely dry, and with the illing material set.

From this heating zone the block proceeds to a tinting or coloringstation F where appropriate pigments or other coloring agents may beapplied to the block face if it be desired that said face exhibitcolorations other than those naturally possessed by the blockconstituents. The coloring agents may comprise, for example,watersoluble or suspendible pigments such as iron oxide, iead chromate,etc., and may be applied to the blocl: face by means of a conventionalspray gun 18. The apparatus and procedure at this station need not beutilized if blocks presenting the natural colorings of their componentmaterials be desired.

Loss of heat by the block during its travel to and from the coloringstation F, as well as by reason of the application of the relativelycool coloring agent if that station be functioning, appreciably reducesthe block temperature below that at which it left the heating zone atstation E, and since the temperature of the block face at the time theglaze coating is applied is important in order that a rapid jell of theglaze material employed may be attained while at the same time securingsatisfactory adhesion of the coating to the block, upon leaving thecoloring station F the block is traversed through a second heating zoneat a station G, provided by a battery of infra red heaters 19. Theseheaters, and the time of exposure of the block to their etect, are socontrolled that upon leaving this second heating zone the temperature ofthe block is on the order of 170 F. to 200 F., as this is most effectivein securing a quick jell of the glaze material here employed.

This material is a transparent thermo-setting polyester resin which isliquid at normal room temperatures, or a mixture of hard and soft resinsof this type, and a thin coating or film thereof is appliedsubstantially uniformly to the block face, as by a spray gun 2), at aglazing station H to which the block is moved by the conveyor 11 uponleaving the second heating zone. As an example of a resin which inpractice hm been found particularly suitable for the purpose there maybe mentioned one which is a reaction product of a dihydric alcohol, suchas a glycol, and a dibasic acid. When applied to blocks heated to theabove mentioned temperatures this material acquires a substantialinitial jell within three to four minutes from the time of application.This quick jell feature is deemed of substantial importance in that,while permitting of sufficient penetration of the block material by theresin to attain a satisfactory bond between the coating and the blocksurface, it at the same time prevents over-absorption of the resin bythe cementitious binder and cavityiilling materials of the block, withresultant appreciable reduction in the quantity of glaze material neededto produce a satisfactory coating.

Complete polymerization or curing of this resin may be secured by theadmixture therewith of a catalyst, such as methyl ethyl ketone peroxide,and/or the further application of heat, in View of which after the filmor coating has attained its initial quick jell, the block is passedthrough a third heating zone provided at a station I by a battery ofinfra red lamps 2l. This zone is so spaced from the glazing station Hthat, at the speed at which the block is advanced by the conveyor il,the resin coating will have attained its initial jell by the time theblock reaches station I, and the said zone is of such length as toeffect complete curing and setting of the resin. Upon leaving this zonethe block preferably is retained on the conveyor for a time adequate forits temperature to drop to a point at which it may be manually handled,if desired, when it reaches the discharge end 22 of the conveyor.

With the conveyor l1 moving at a speed on the order` of eight feet perminute a bloclt may be completely processed as described above withinfteen minutes from the time it is placed on the head end of theconveyor; and with blocks of conventional cinder block size placed uponthe conveyor in relatively close proximity, as indicated in FIG. l ofthe drawing, a production rate of at least six blocks per minute may bereadily attained in a single line.

As previously indicated, use of the coloring station F is optional,depending upon whether tinted or uncolorcd blocks are to be produced. lfonly blocks exhibiting the natural colorings of their constituents areto be made, the said station may be omitted entirely, in which caseeither the first or the second heating zone may be climinated. However,it is preferred to arrange the installation substantially as indicatedin the drawing in order that blocks of either type may be produced atwill.

While the foregoing description has made reference to the processing ofonly a single face ot a block, if it be desired or intended that morethan one block face be exposed to view in the finished structuralelement, the blocks may be returned to the head end of the conveyor 11and such additional face or faces processed in the manner abovedescribed.

What is claimed is:

1. rEhe method of treating molded and cured blocks composed of acementilious binder component and discrete aggregates whereby to producedecorative masonry clements, said method comprising: uninterruptedlyadvancing such a block along a predetermined path and, concomitantlytherewith, sequentially dressing a face of the blocl: to produce thereona smoothed but porous and pitted surface which displays the contrastingcolorations of the respective block constituents; applying a plastic,settable composition to said face and working it into the depressionsand openings therein to till the same; removing excess fillingcomposition from the block face, to preserve the color contrasts of theblock constituents appearing therein; heating the block to a temperaturesutiicient to produce a rapid jelling of a liquid resinous materialapplied thereto; coating the dressed face of the so-heated block with alm of a transparent thermosetting polyester resin; further heating theblock after attainment by snch resin coating of the initial jell inducedtherein by said block temperature, to complete the settling theerof; andcooling the block.

2. The method dened in claim l, wherein the filling composition embodiesa liquid component which is evaporated by the heating of the block, withresultant setting such composition.

3. The method defined in claim l, wherein the filling compositioncomprises a Water-asbestos cement mixture, the water of which isevaporated by the heating of the lock.

4. The method defined in claim l, wherein the removal f the excessilling composition is effected by subjecting said face to the action ofa flushing liquid.

5. The method defined in claim 4, wherein subsequent to the iiushing ofthe dressed face of the block, said tace is subected to a squeegeeaction to remove at least a major portion of any flushing liquidremaining thereon and etect a smoothing or the filling compositionretained in the cavities of said face.

6. The method defined in `claim 1, wherein a coloring agent is appliedto the block face While the block is at an elevated temperature.

7. The method of making decorative masonry blocks which comprises:uninterruptedly advancing a molded and cured cernentitious,aggregate-containing block along a predetermined path and, concomitantlywith such con` tinuous movement, sequentially dressing a face of theblock to provide thereon a relatively smooth but porous and pittedsurface which displays the contrasting colorations of the respectiveblock constituents; applying a plastic, settable cavity-llingcomposition to said face and Working it into the depressions andopenings therein to fill the same; subjecting said block face to theaction of a flushing liquid, to remove excess cavity-filling compositiontherefrom whereby to preserve the color contrasts of the blockconstituents appearing therein; subjecting said block face to a squeegeeaction to remove a substantial portion or" any liquid remaining thereonand effect a Smoothing of the lling composition retained in the facecavities; elevating the temperature of the block to a point suicient toremove any remaining moisture therefrom; applying a coloring agent tosaid block face While the block is at said elevated temperature;bringing the block to a temperature Within a range of approximately 170F. to 200 F.; spraying upon said block face while at such temperature asubstantially uniform film of a liquid transparent thermosettingpolyester resin which will jell rapidly Within said temperature range;further heating the block upon completion of the initial quick jell ofthe resin coating to complete the setting thereof; and cooling theblock.

References Cited by the Examiner UNITED STATES PATENTS 1,099,837 6/14Black.

1,185,800 6/16 Hoiles 25-1 1,578,091 3/26 Perkins.

1,619,734 3/27 Jeppson et al.

2,195,910 4/40 Welch 50-268 2,629,135 2/53 Johnson.

2,751,775 6/56 Sergovic.

2,805,448 9/57 Rubenstein.

2,814,836 12/57 Russell.

2,835,996 5/58 De Paoli.

2,878,666 3/59 Drummond 50-268 2,946,110 7/60 Lang 25-1 FOREIGN PATENTS821,897 10/59 Great Britain.

VJILLIAM D. MARTN, Primary Examiner.

WLLAM 1. MUSHAKE, WlLLIAM I. STEPHENSON,

RCHARD D. NES/IUS, Examiners.

1. THE METHOD OF TREATING MOLDED AND CURED BLOCKS COMPOSED OF ACEMENTITIOUS BINDER COMPONENT AND DISCRETE AGGREGATES WHEREBY TO PRODUCEDECORATIVE MASONRY ELEMENTS, SAID METHOD COMPRISING: UNINTERRUPTEDLYADVANCING SUCH A BLOCK ALONG A PREDETERMINED PATH AND, CONCOMITANTLYTHEREWITH, SEQUENTIALLY DRESSING A FACE OF THE BLOCK TO PRODUCE THEREONA SMOOTHED BUT POROUS AND PITTED SURFACE WHICH DISPLAYS THE CONTRASTINGCOLORATIONS OF THE RESPECTIVE BLOCK CONSTITUENTS; APPLYING A PLASTIC,SETTABLE COMPOSITION TO SAID FACE AND WORKIGN IT INTO THE DEPRESSIONSAND OPENINGS THEREIN TO FILL THE SAME; REMOVING EXCESS FILLINGCOMPOSITION FROM THE BLOCK FACE, TO PRESERVE THE COLOR CONTRASTS OF THEBLOCK CONSITITUENTS APPEARING THEREIN; HEATING THE BLOCK TO ATEMPERATURE SUFFICIENT TO PRODUCE A RAPID JELLING OF A LIQUID RESINOUSMATERIAL APPLIED THERETO; COATING THE DRESSED FACE OF THE SO-HEATEDBLOCK WITH A FILM OF A TRANSPARENT THERMOSETTING POLYESTER RESIN;FURTHER HEATING THE BLOCK AFTER ATTAINMENT BY SUCH RESIN COATING OF THEINITIAL JELL INDUCED THEREIN BY SAID BLOCK TEMPERATURE, TO COMPLETE THESETTING THEREOF; AND COOLING THE BLOCK.